The present invention generally relates to apparatus for connecting equipment so that hydraulic and other fluids can be transferred between equipment and, more specifically, to apparatus for connecting equipment where fluids may be pressurized and where spillage and leakage are highly undesirable
In many applications, flexible conduits such as hoses and tubing are inappropriate for connecting equipment, and equipment may be heavy and cumbersome to manipulate in order to align connectors needed to transfer hydraulic and other fluids. Connectors are needed to enable quick and reliable connections between such equipment.
Often the hydraulic fluid is under pressure and provides energy to perform some mechanical task. Connectors are needed that can be coupled and decoupled quickly and without requiring tools. Also, connectors must provide non-leaking connections. Furthermore, connectors are needed that automatically close when decoupled so that the fluid does not continue to flow out of the decoupled connector.
There are many examples of fluid connectors in the known art, most of which are intended for use with flexible conduit such as hose and tubing. Such connectors rely on a user to provide alignment by joining the hose coupler by hand. Many of them include spring operated internal valves to prevent fluid leakage when disconnected. They often include spring-loaded latching elements to enable “push-to-connect” functions. The spring-operated elements of such couplers can require significant force be overcome when attaching to the connecters. Furthermore, the latching elements can require manual release in order to decouple form the connector. This makes these connectors unsuitable for applications where heavy or fixed-position appliances need to be fluidly connected and where flexible conduit is not suitable.
One coupler in the prior art, U.S. Pat. No. 4,222,411 by Herzan, has a coupler body with two opposing coaxial female connectors for accepting two separate male connectors. The coupler body is substantially cylindrical with female connections aligned axially at either end of the cylinder. The particular coupler can accept one threaded male connector and one push-to-connect nipple.
The Herzan coupler has an inner plug that slides axially within the coupler body, the plug being movable via a cam-action rotary knob that extends radially from the cylinder body. The plug provides the female connection for the threaded male connector. In a closed position, a movable stopper within the coupler body seals off the opposite female connections from each other. In an open position, the rotary knob moves the inner plug with the threaded connection axially towards the opposite connection, in the process shifting the movable stopper to open a fluid path between the two female connections.
The Herzan coupler requires relative movement between the two attached connecters to effect coupling and decoupling, so it is not appropriate for fixed mounting to two hydraulic appliances. In addition, it also relies on spring-operated latches and valves to hold and seal the connectors.
Another connector from the prior art, U.S. Pat. No. 6,283,151 to Countryman et al, can be fixedly mounted to one appliance, yet requires the mating appliance be inserted into the coupler to form the connection. Like the aforementioned Herzan coupler, it has spring operated latches and internal valves.
As can be seen, there is a need for fluid connectors that can be fixedly mounted to hydraulic appliances and then coupled and decoupled without depending on flexible conduit and without requiring movement of either appliance in order to facilitate coupling and decoupling. Also, there exists a need for fluid connectors that can be employed without restoring forces that must be overcome in order to couple to the connector. Such restoring forces, usually the result of spring latches and spring operated internal valves, can be significant and make both mounting of fixed appliances and coupling to the fluid connector unnecessarily difficult.